Combinatorics

Please answer a,b,c!

1. For each of the following block designs, determine if the design is a BIBD and if so, determine its parameters v, b, r, k, and > . a) V = { 1, 2, 3, 4 } Blocks: { 1,4}, {3,4} , { 2, 3, 4 } b) V = { a, b, c, d Blocks: { a, b, c, d }, { a, c, d, e }, {a, b, d, e }, {a,b,c, e}, {b, c, d,e} c) V = { 1, 2, 3, 4,5} Blocks: { 1, 2, 3 } , { 2, 3, 4 } , { 3, 4, 5 }, { 1,4,5}, { 1, 2,5 } 1. For each of the following block designs, determine if the design is a BIBD and if so, determine its parameters v, b, r, k, and > . a) V = { 1, 2, 3, 4 } Blocks: { 1,4}, {3,4} , { 2, 3, 4 } b) V = { a, b, c, d Blocks: { a, b, c, d }, { a, c, d, e }, {a, b, d, e }, {a,b,c, e}, {b, c, d,e} c) V = { 1, 2, 3, 4,5} Blocks: { 1, 2, 3 } , { 2, 3, 4 } , { 3, 4, 5 }, { 1,4,5}, { 1, 2,5 }